Influence of Equation-of-States on Supercritical CO2 Combustion

2020 ◽

Author(s):

K. R. V. (Raghu) Manikantachari ◽

Scott M. Martin ◽

Ramees K. Rahman ◽

Carlos Velez ◽

Subith S. Vasu

Keyword(s):

Supercritical Co2 ◽

Carbon Capture ◽

Flame Structure ◽

Compressibility Factor ◽

Operating Conditions ◽

Binary Interaction ◽

Binary Interaction Parameter ◽

Combustion Modeling ◽

Equation Of States ◽

Supercritical Combustion

Abstract Fossil fuel based direct-fired supercritical CO2 (sCO2) cycles are gaining the attention of industry, academia and government due to their remarkable efficiency and carbon capture at high-source temperatures. Modeling plays an important role in the development of sCO2 combustors because experiments are very expensive at the designed operating conditions of these direct-fired cycles. Inaccurate density estimates are detrimental to the simulation output. Hence, this work focuses on comprehensive evaluation of the influence and applicability various equation-of-states (EOS) which are being used in the supercritical combustion modeling literature. A state-of-the-art supercritical combustion modeling methodology is used to simulate counter-flow supercritical CO2 flames by using various equation-of-states. The results show that, using the corresponding state principle to evaluate compressibility factor is not accurate. Also, van der Waal type EOSs predictions can be as accurate as complex Benedict-Webb-Rubin EOSs; hence van der Waal EOSs are more suitable to simulate sCO2 combustor simulations. Non-ideal effects are significant under the operating conditions considered in this work. The choice of EOS significantly influences the flame structure and heat release rate. Also, assuming the binary interaction parameter as zero is reasonable in sCO2 combustion simulations.

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Influence of Equation-of-States on Supercritical CO2 Combustion Mixtures

Journal of Energy Resources Technology ◽

10.1115/1.4048666 ◽

2020 ◽

Vol 143 (6) ◽

Cited By ~ 1

Author(s):

K.R.V. (Raghu) Manikantachari ◽

Ramees K. Rahman ◽

Scott M. Martin ◽

Carlos Velez ◽

Subith S. Vasu

Keyword(s):

Supercritical Co2 ◽

Carbon Capture ◽

Flame Structure ◽

Compressibility Factor ◽

Operating Conditions ◽

Binary Interaction ◽

Binary Interaction Parameter ◽

Combustion Modeling ◽

Equation Of States ◽

Supercritical Combustion

Abstract Fossil fuel based direct-fired supercritical CO2 (sCO2) cycles are gaining the attention of industry, academia, and government due to their remarkable efficiency and carbon capture at high-source temperatures. Modeling plays an important role in the development of sCO2 combustors because experiments are very expensive at the designed operating conditions of these direct-fired cycles. Inaccurate density estimates are detrimental to the simulation output. Hence, this work focuses on comprehensive evaluation of the influence and applicability of various equation-of-states (EOS) which are being used in the supercritical combustion modeling literature. A state-of-the-art supercritical combustion modeling methodology is used to simulate counter-flow supercritical CO2 flames by using various equation-of-states. The results show that using the corresponding state principle to evaluate compressibility factor is not accurate. Also, van der Waal type EOSs predictions can be as accurate as complex Benedict–Webb–Rubin EOSs; hence van der Waal EOSs are more suitable to simulate sCO2 combustor simulations. Non-ideal effects are significant under the operating conditions considered in this work. The choice of EOS significantly influences the flame structure and heat release rate. Also, assuming the binary interaction parameter as zero is reasonable in sCO2 combustion simulations.

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Solubility of vitamin A in supercritical CO2: experimental study and thermodynamic modeling

Scientific Reports ◽

10.1038/s41598-021-92374-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Gowhar Ahmad Naikoo ◽

Mohammad Saeedi Zadegan ◽

Mona Zamani Pedram ◽

Israr Ul Hassan ◽

Waqar Ahmed ◽

...

Keyword(s):

Experimental Data ◽

Vitamin A ◽

Supercritical Co2 ◽

Pressure Range ◽

Solubility Data ◽

Mixing Rules ◽

Critical Properties ◽

Body System ◽

Relative Deviation ◽

Equation Of States

AbstractOne of the best methods of extracting Vitamin A, as a helper of the immune body system and vision, was measured in supercritical carbon dioxide (SC-CO2); Mole fractions were gained at practical conditions in which the temperature was in the range of 303–323 K and the pressure range was 90–235 bar, respectively. Moreover, four Equation of States [Soave–Redlich–Kwong, Peng–Robinson, Stryjek–Vera and Dashtizadeh–Pazuki–Taghikhani–Ghotbi (DPTG)] were compared with the experimental data. Also, the mixing rules of Van der Waals (vdW1 and vdW2) selected to correlate the solubility data of vitamin A. The outcomes indicate that each of EOSs coupled with vdW2, as a method of estimating the physicochemical and critical properties, were correlated with the solubility data of vitamin A in SC-CO2 with more accuracy, in comparison with vdW1. Among the cubic EOSs, the DPTG model with vdW2 generated the most suitable correlation with the percentage average absolute relative deviation (Average Absolute Relative Deviation%) of 6.

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